kitzi jewelry wholesale How to make chemical teaching aids specifically include: teaching aids, simple production, characteristics of teaching aids, and use objects

egyptian jewelry box wholesale Chemistry is a discipline based on experiments. In classroom teaching, demonstration experiments are an important part of classroom teaching. It is not only intuitive, easy to understand, and persuasive, but also can mobilize students 'active thinking and stimulate students' interest in learning. Over the years, in the inorganic chemical textbooks, when telling "water ionization of water", it is often mentioned that "pure water is generally considered to be non -conductive, but when the precision instrument is determined, the water is found to have weak conductivity." There is no demonstration experiment in this part. Not only is the teacher's teaching feel empty, it is also difficult for students to understand. Due to the restrictions of various conditions, general schools do not have such precise instruments. In order to meet the teaching needs, we have made a simple water conductive detector.

It simple pure water conductors is easy to get materials, low cost, simple production, easy operation, easy to carry, easy to display in classroom demonstration.

1 The principle of making the production

In two electrodes in a small cup with pure water, and connected in the circuit in series:
n A very weak electrolyte, only a small part of the H2O molecular ionization into H and OH-, so the water conductive capacity of the water is very weak, and the incandescent light bulbs cannot be glowed, and the pupa in the solar lamp in the bubbles is appropriate. When passing), it can leave the gaseous electricity between the dual metal sheets and generate the visible glow. This confirms that pure water can be weak.

2 Materials for

2 (15W) of incandescent light bulbs, 1 daylight lamp enables (bubble), 2 threaded lights, 2 50 ml burn cups, 2 cups, 2 2 power switches, 4 waste battery core rods, wires, wooden boards.

3 The production process

(1) Remove the glass on the light bulb with a 15W incandescent bulb and remove the tungsten wire.

(2) Take the sunlight inspiration to the shell, take out the bubble, and welded the foam on the light bulb instead of the foam, and the outer truncated test tube is covered, which is made into a bubble bulb.

(3) The other intact incandescent bulb and 氖 bulb are connected in the circuit.

(4) assembled the power switch, electrode, and bulbs on the wooden frame that is made in advance, that is, a simple pure water conductors.

4 How to use

P poured pure water in two small cups, insert an electrode (battery core rod), connect the AC power supply (220V), turn on the power switch, you can, you can, you can Observed the incandescent bulbs, and the light bulbs emitted red light.